Scored smart card

ABSTRACT

The invention relates to a SIM ( 2 ) card in a first format, with an electronic module ( 4 ). The card body comprises a score line ( 6 ) surrounding the electronic module ( 4 ) in order to define the second card format ( 3 ). The said score line ( 6 ), comprises residual matter thickness that is smaller than the thickness of the card body. The thickness of the residual matter comprises a first thickness ( 9 ) over a first part of the score line ( 6 ), at least one second thickness ( 10 ) smaller than the first thickness ( 9 ) over a second part of the score line and at least one residual thickness change zone ( 11, 17 ), where the said thickness change zone is a gradual thickness change zone ( 11, 17 ) that goes from the first thickness to the second thickness.

BACKGROUND

The invention relates to a scored smart card and particularly theprofile of the score.

SIM (Subscriber Identity Module), cards, also called UICC (UniversalIntegrated Circuit Card) cards, are smart cards defined by the standardETSI TS 102 221 of the European Telecommunications Institute. The ETSIhas defined three SIM card formats. The first format is identified bythe ETSI as the ID-1 UICC format, the format commonly called ‘creditcard’ format, which is also defined in the standard ISO 7816-1. Thesecond format is identified by the ETSI as the Plug-in UICC format, themost common format today with a card size of 25 mm by 15 mm, also calledthe second-generation format or 2FF format. The third format isidentified by the ETSI as the Mini UICC format, the recently introducedformat with a card size of 15 mm by 12 mm, also called thethird-generation or 3FF format.

Smart card manufacturers are used to making a card body in the ID-1 UICCformat in which card body formats of the Plug-in UICC and Mini-UICCsizes are placed, nested with one another and separated by scored zones.Scored zones may be achieved by a separating score line between the cardbodies, which are joined to each other by tabs or by a so-calledperimeter score.

The separating score line is commonly used because it makes it possibleto hold the cards together well, while making it easy to separate them,breaking off one tab after another. However, this technique has onedrawback, due to the score line, if it is used between the 2FF and the3FF format. That is because some connectors receive the card by sliding,and have very thin contact pads that get stuck in the score line, thusdamaging the connector and making the telephone unusable.

The perimeter score is a score made by reducing the thickness of theentire perimeter of the card body, leaving residual thickness that issmaller than the thickness of the card. The thickness of the card is 800μm, so such a score leaves a residual thickness of a few hundred μm.This type of score remedies the problem presented above by theseparating score line between the formats 2FF and 3FF. However, theperimeter score has the drawback of either being difficult to detachwhen the thickness of the residual matter left by the score is too greator being liable to be detached unintentionally when the residualthickness is too small. Additionally, in order to ensure highmanufacturing efficiency, a card must be made which is compatible withthe injection moulding method.

SUMMARY

The invention is aimed at offering a new solution to remedy the problemsdescribed above. On a smart card with a card body in the first cardformat and an electronic module, the card body comprises a score linesurrounding the electronic module which defines a second card format,wherein the residual thickness of matter of the score line is smallerthan that of the card body. The invention is characterised by a residualmatter thickness which comprises a first thickness on a first part ofthe score line, at least a second thickness smaller than the firstthickness on a second part of the score line and at least one residualthickness change zone. The said thickness change zone is a gradualthickness change zone from the first thickness to the second one.

The use of the first thickness makes it possible to hold the card on thefirst part and avoid the unintentional detachment of the card in thesecond format. The use of a second, smaller thickness makes it possibleto have a part that is easy to detach to start detachment. The use ofthe gradual thickness change zone makes it easier to make the mould andachieve a gradual increase in force during detachment.

Preferentially, the first part and the second part are separated by apivot axis, which is an axis that substantially separates the secondcard body format into two substantially equal parts. The pivot axisdemarcates the zone on which the detachment can start.

The residual thickness may be asymmetrical in shape. The residualthickness may be offset in relation to the thickness of the card body.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood and other particularities andbenefits will become clear in the description below, which refers to theattached drawings, where:

FIG. 1 illustrates a first smart card format embodying the invention,

FIG. 2 illustrates a second smart card format embodying the invention,

FIGS. 3 and 4 illustrate different details for a better understanding ofthe invention,

FIGS. 5-7 represent views of sections along a plane going through ascore line,

FIGS. 8-9 represent view of sections along a plane perpendicular to ascore line

FIGS. 10-14 illustrate alternative embodiments

DETAILED DESCRIPTION

FIG. 1 represents a smart card with a first card body 1 in the creditcard format that supports a second card body 2 in the 2FF format and athird card body 3 in the 3FF format. An electronic module 4 is mountedon the third card body. The electronic module 4 is a conventional modulecomprising an integrated circuit and a connector supporting six or eightcontact pads. The first, second and third card bodies are demarcated bybreaking zones 6 and 8. The breaking zones further define the differentcard bodies and are placed so that the electronic module is positionedon the three card bodies considered independently of each other, in amanner known in the state of the art.

The first card body 1 is separated from the second card body 2 by thefirst breaking zone 8. This breaking zone is made up of a separatingscore line, with for example three tabs 5 and 7, the tabs 5 beingsmaller to break easily and allow pivoting at the start of the break oftab 7, up to the break of that tab 7. The second card body 2 isseparated from the third card body 3 by the second breaking zone 6. Thesecond breaking zone is made in accordance with the invention and willbe detailed below.

The card represented in FIG. 1 is a card made and sold in ID-1 format.However, SIM cards can also be made and sold directly in 2FF format asrepresented in FIG. 2. The card is then only made up of the second cardbody 2 supporting the third card body 3 separated by the second breakingzone 6. The invention essentially relates to this second breaking zone6, and in the document below, the card body 1 and the first breakingzone 8 will not be mentioned, even though these two elements may verywell be present. The invention could also be used for the first breakingzone 8 even though it is not strictly necessary.

In FIG. 3, it can be seen that the breaking zone 6 is a score line thatcomprises five sides named A, B, C, D and E for future reference. InFIG. 4, there are five lines that substantially separate the surface ofthe third card body into two substantially equal parts. The lines X andY are the median lines of the 3FF format, which pass through the middleof the third card body and are parallel to the edges of the said body.The lines D1, D2 and D3 are straight lines that go through substantiallyopposite vertices and define two parts with substantially the same area.In that context, substantially equal can mean equal with 10% tolerance,the important feature being that the line divides the card into twoparts with a significant surface.

The breaking zone 6 in the invention is made up of a score line wherethe thickness of the residual matter comprises a first thickness 9called the large thickness, for example 200 μm, and a second thickness10 called the small thickness, for example 120 μm. The first thickness 9illustrated in the section in FIG. 5 ensures proper card holding. Thesecond thickness 10 illustrated in FIG. 6, makes the score easier todetach. Advantageously, any of the lines X, Y, D1, D2 or D3 may be usedas the pivot axis with, on one side of the line, the first thickness andon the other side of the line, the second thickness.

For example, if the line Y is considered to be the pivot axis, it ispossible to have the first thickness on the side A and the secondthickness on the sides C and D. The sides B and E support firstly thefirst thickness and secondly the second thickness separated by atransition zone. A user who presses the third card body will break thesides C and D fairly easily. If the user does indeed wish to separatethe second and third card body, they must keep pressing the third cardbody, and the sides C and D that are already separated can then act asthe start of the break for the sides B and E, then the strongest side A.It is to be noted that once a part of the card is separated, thedetaching force can be reduced as shearing is gradual along the scoreline of the second thickness and not on the totality of the score.

If the pressure applied on the third card body is not deliberate, thesides C and D as they cede indicate to the user that they risk detachingthe cards. Fortunately, the stronger sides A, B and E maintain the thirdcard body 3 in the second card body 2.

Thus, a score line is made that can avoid unwanted detaching, at thesame time allowing easy separation of the second and third card bodies.

If the line D1 is taken as the pivot axis, the change in thickness willstraddle the sides B and C on the one hand and A and E on the other.

In order to mould the cards, it is preferable to have a gradualtransition zone to improve mould removal. The gradual transition zone 11is represented in FIG. 7. The gradual change in thickness also offersthe benefit of gradually increasing the shearing force required as thethird card body is freed and therefore as the lever arm offered by thedetached part of the third card body increases. That gradual change maybe used over the entire length of the side or only on one part of theside, for example 5 mm.

It must be noted that the first and second thicknesses 9 and 10 can varydepending on the surrounded surfaces; thus, the first thickness may forexample vary between 100 and 300 μm and the second thickness may forexample vary between 30 and 230 μm. These thicknesses may also varydepending on the materials used. Typically, there must be a differencebetween the first and second thicknesses ranging between 70 and 150 μm.

As regards the score profile, reference is made to FIGS. 8 and 9, whichshow the two types of profile. FIG. 8 represents a so-called half Vprofile with symmetrical score lines 13 and 14 on each side of the card.The opening of the half V on the surface is proportional with the depthof the score line, while being very much smaller than the depth of thatscore line.

In FIG. 9, the score line is made with V scores 15 and 16; the openingof these scores is slightly larger than the half V scores but is alsovery limited. The V opening makes it possible to also allow better mouldremoval.

Regardless of the profile selected, the opening on the surface dependson the opening angle of the V or half V, which may range from 8° to 45°,and the penetration depth. It is absolutely possible to limit theopening on the surface to 300 μm. With such an opening width, the riskof the contact pads of a reader sticking in the notch when the card isused with the 2FF format is remote.

In terms of embodiment, that score may be achieved by moulding. Themould must be made by taking account of the profile of the score in theinvention and moulding is performed normally using a known technique. Ofcourse, the choice of the type of opening will depend on the materialsselected for the mould in order to allow better mould removal.

The person of the art will understand that many alternatives using thetwo thicknesses in the invention are possible. In particular, the use ofall the lines indicated is possible and other lines may also be used aspivot axes demarcating the zone with the first thickness and the zonewith the second thickness.

Other alternatives may also be envisaged. For example, symmetricalnotches may not be used. The cost of a moulding die with no heightvariation being lower, asymmetrical score profiles may be used. Thus,the first and second thicknesses 9 and 10 may be offset as representedin FIGS. 10 and 11. A single mould die can handle the thicknessvariation. Thus the gradual change 17 is also only made on one side, andthe other side does not change levels.

It is also possible to have dissymmetrical scores 13 to 16, as shown inFIGS. 13 and 14, only to provide on one side a score 14 or 16 with alimited and constant opening, for example on the side of the contacts.The residual thickness is then offset in relation to the thickness ofthe card body. That may further limit the risk of jamming a contact pad.

The invention claimed is:
 1. A smart card comprising: a first card bodyin the credit card format that supports a second card body in the 2FFformat and a third card body in the 3FF format and an electronic module,a score line surrounding the electronic module and defining said 3FFformat, the said score line comprising all along the score line aresidual matter thickness that is smaller than the thickness of thesecond card body, the residual matter thickness comprises: a firstthickness over a first part of the score line, at least a secondthickness smaller than the first thickness over a second part of thescore line and at least one residual thickness change zone, the saidthickness change zone being a gradual thickness change zone that startswith the first thickness and proceeds to the second thickness.
 2. A cardaccording to claim 1, wherein the first part and the second part areseparated by a pivot axis, which is a line that substantially separatesthe second card body format into two substantially equal parts.
 3. Acard according to claim 1, wherein the residual thickness isasymmetrical in shape.
 4. A card according to claim 1, wherein theresidual thickness is offset in relation to the thickness of the cardbody.
 5. A card according to claim 1, which is made by moulding.